Help for Your Brain: A Great Gift!

Transcranial Direct Current Stimulation ( tDCS ) has come a long way in just a few years.  This incredible technology can relieve depression, improve memory, speed learning, and more and is slowly moving toward main-stream as new research, products, and government approvals come along. It’s been the darling of university research centers since Scientific American published a ground-breaking article about tDCS in 2011 ( see https://www.scientificamerican.com/article/amping-up-brain-function/

The Go Flow 4 comes in an attractive zipper case ready for travel.

Now foc.us (www.foc.us) has another product in their portfolio of brain stimulation and EEG related products – the Go Flow 4 – which is available in the US from http://www.caputron.com for $244. This complete kit includes a versatile, compact tDCS device, battery, electrodes, wires, headband and basic instructions.

The Go Flow 4 case contains all you need except water!

Here’s How It Works

The Go Flow 4 tDCS device passes an extremely small direct current through your brain via specific locations on your scalp in order to enhance or reduce a particular kind of brain activity.  It is thought that the excitation level of various brain cells is modified by the current and can result in reduction or elimination of depression symptoms, improved memory, quicker learning (including physical task learning), improved sleep, and more.  Electrodes must be placed correctly and 20 minute sessions must be repeated daily for a number of days in order to receive the full benefit of tDCS. tDCS is used by the US military, various mental health professionals, and pioneering individuals around the world. 

My famous tDCS test-head with foc.us electrodes and headband ready for a tDCS session.

To use the Go Flow 4 you follow some simple steps:

  1. Attach the battery to the Go Flow 4 device
  2. Place electrodes in the headband at the desired button-hole locations and moisten the electrode sponges with tap water or saline water.
  3. Set the current and duration for the session using the rocker switch on the Go Flow 4
  4. Place the headband on you head and position as desired. Start the tDCS session and monitor current and time remaining using the LED lights on the tDCS device

More detailed instructions are included with the Go Flow 4 and should be read carefully before use.

While most tDCS scenarios (called “montages”) use two electrodes and a current of two milliamps or less, the Go Flow 4 has some advanced capabilities that permit the use of four electrodes simultaneously, a current of up to four milliamps, and a special mode call slow oscillating tDCS (sotDCS.)  More on these in my next post.

Using the Go Flow 4

My experience with the Go Flow 4 is very positive. It is easy to use, very convenient, great for portable and travel use, and delivers predictable and reliable tDCS sessions. I love that you no longer need to disconnect the battery after use as a prior version of the Go Flow required.  

Before you buy this or any tDCS device, do your homework.  tDCS is not for everyone. Read about tDCS (google search at least) and decide if it is right for you. I can also suggest you visit:

www.speakwisdom.com
www.caputron.com
www.foc.us
www.diytdcs.com
reddit.com/r/tdcs

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Electrode Wars! (Well Not Quite)

IMG_3163

I’ve written a ton about all the great potential of brain stimulation and particularly tDCS. There are many studies and plenty of anecdote related to improving memory and creativity, reducing chronic pain, treating depression, etc. More about all of that later.

The National Center for Health Statistics just announced that the U.S. suicide rate has climbed to a 30-year high. This coupled with data that we have long had in hand – about 10% of the U.S. population is clinically depressed, that there are about 40,000 suicides in the U.S. every year, and that only about 20% of the people needing depression related treatment actually get it – tells you that our national mental health system is a failure.

tDCS* has emerged as a treatment method that is inexpensive, simple, safe, and has good effect for many of those who use it for depression related symptoms. tDCS use by professionals continues to grow and certainly the do-it-yourself (DIY) community is enthusiastic about it. tDCS requires placing electrodes on the head and passing a very tiny current between them in order to nudge the brain towards proper functioning (or enhancement.)

There are two popular kinds of electrodes, stick-on and sponge. Stick-on electrodes are simple and very useful when hair won’t get in the way. They are used once (or a few times for some) and discarded.  Sponge electrodes are preferred by most using tDCS as it can be used on skin or over hair, can be reused many times, and has a low cost per use.

Amrex has been the big dog in sponge electrodes for the tDCS world for a long time but competitors are emerging and I’d like to cover two of them here. First, Caputron (www.caputron.com) introduced a nice “clone” of the Amrex electrode some time ago and continues to offer it today.  It is available as a 3×3 (typical size used in tDCS) or 2×2 shell (about 2×2 and 1.1 x 1.1 sponge contact dimension). The Caputron electrode does have two distinct advantages – first they are more flexible and conform to curves of the skull more easily, and second they are much less expensive! A 3×3 electrode is only $12! They, like the Amrex electrodes have a banana jack for connection and a stainless steel screen behind the sponge for even current distribution. Also like Amrex electrodes, you can buy replacement sponges from Caputron (about $1 each) – or make your own from kitchen sponges.

IMG_3155
(The Caputron shell – orange – with the sponge removed. Note the stainless screen and banana jack. An Amrex shell is shown too – gray.)

Caputron also offers a nice, general purpose strap system that can be used with any brand of sponge electrodes. It’s called the Caputron Universal Strap System and is made of rubber (not latex). There are two independent straps that are marked with a centimeter scale that makes accurate placement of electrodes easy. The system is stretchy and very adjustable for position and head size. I really like this strap system and you will too – if you don’t mind the $75 price.

IMG_3161
(The Caputron Universal Strap on my much abused “test head”. The strap is versatile and easy to use.)

foc.us (famous for the foc.us V2 brain stimulation device and the new Go Flow tDCS device) is just releasing a new sponge electrode system  for the V2 and Go Flow that is very interesting! It consists of a rubber-like shell (about 2×2) and sponges that when inserted result in a 1.25 x 1.25 inch sponge contact area. To connect to the foc.us sponge electrodes, you need a special V2/Go Flow cable that attaches magnetically to the electrode shell. That means the problem of having an electrode jerked off of your head should you become tangled somehow goes away. This is a vastly better connection technology than the banana plug and socket used by many manufactures.

IMG_3146
(The new foc.us electrode shell and sponge. Note the magnetic ends on the wires for easy attachment to the electrode shells. A new production white Go Flow and 9 volt battery are also shown.)

foc.us is also releasing a companion head strap with strategically placed cutouts that allows easy and repeatable placement of the electrodes on your head. This new strap ships as part of the “Go Flow Pro” which includes the tDCS device, wires, strap, electrode shells (and sponges) and will be available for separate purchase too.

go-flow-pro-large
(The new electrode shells, strap, and Go Flow with battery. Note: some electrode setups may require two straps.)

All of the items mentioned in this blog post (including Amrex and foc.us) can be purchased from Caputron (www.caputron.com).  It’s great to have a dealer here in the U.S. that is carrying a huge variety of devices and accessories. I suggest you visit their web site and have a look.

There are many articles about tDCS available on my blog ( www.speakwisdom.com ) and via www.diytdcs.com .

*transcranial direct current stimulation

 

 

What Should I Buy If I’m New to tDCS?

 

++++ UPDATE AGAIN +++++ UPDATE AGAIN +++++ UPDATE AGAIN +++++

Great News! Caputron has just become a dealer for foc.us products. This means a US source for foc.us products (faster, less expensive shipping, support, etc.) See http://www.caputron.com/transcranial-electrical-stimulation/49-focus-go-flow-pro-tdcs-starter-kit.html

++++ UPDATE +++++ UPDATE +++++ UPDATE +++++

In mid-March of 2016, foc.us released a version of the Go Flow with sponge electrodes. This now becomes my “ideal” for someone new to tDCS. Sponge electrodes are very versatile and are reusable. The new “Go Flow Pro” includes the tDCS device, wire, sponge holders, sponges, and headband – all for $99 plus shipping (from London).

go-flow-pro-large
(The new Go Flow Pro. Image does not show connecting wire or sponges which are included.)

I’m leaving the rest of the post (below) in case you prefer stick-on electrodes or wish to make your own connecting cables.

+++++ FEB 2016 POST BELOW +++++ FEB 2016 POST BELOW +++++

In the last few years I’ve written plenty about tDCS (transcranial direct current stimulation), what it can do, various tDCS devices, etc. It’s been fun and gratifying to watch the whole “brain hacking” arena develop and grow – to the point that a good level of maturity has been obtained. Thousands of people have improved their lives in significant ways through tDCS – improving their learning/memory, easing depression and chronic pain, improving athletic ability, and much more.

I frequently get asked “what should I buy if I want to try tDCS?” The good news is that there are now plenty of good tDCS devices in the marketplace. A simple Google search for “tDCS device” will reveal many possible choices. If I were getting started in tDCS I would strongly consider the following (my opinion – yours may vary!):

  1. tDCS Device: My current favorite is the foc.us Go Flow ( http://www.foc.us/focus-go-flow-tdcs-brain-stimulator ) You can buy this cool little device for $39.99 plus shipping!  It is tiny (easy to carry in your shirt pocket), versatile, and does all the important things a tDCS device should do. The kit includes the tDCS device, connecting wire, stick-on electrodes, and a 9 volt battery.IMG_2912 (3)
  2. Adapter Cable: You will want a cable to adapt the Go Flow to standard tDCS cables. I would order ( http://www.foc.us/tdcs-tens-cable-adaptor ) It is $9.00 plus shipping (order at the same time you get the Go Flow to save on shipping.)
    cableadapter_2
  3. Electrodes: Most people do best using sponge electrodes. I prefer Amrex 3×3 electrodes.  They are available from many medical supply houses (Caputron Medical), Amazon, and more. They cost around $20 each and you will need two. The sponge can be easily replaced with a cut kitchen sponge when necessary.
  4. You will need a cable to connect the electrodes to the Go Flow and its adapter cable.  I suggest ( http://www.bluemoonhealth.com/tens_supplies_pages/banana_wires.htm ) It’s $6.95 plus shipping. There are other suppliers if you prefer.
  5. Last, you will need a simple headband to hold the electrodes in place for your tDCS sessions.  Almost any headband will do.  It needs to hold the electrodes firmly, but not so tight as to be uncomfortable.  I use Suddora Athletic Headbands – available from Amazon and others for about $6.00
    51j+CDVPtBL._SL1000_

Conclusion

So what does it all add up to? You will spend a little over $100 to buy all of the above (and pay shipping). This is a very reasonable cost when compared to that of long term medication use or the price of fancier brain hacking devices.  I use the exact setup shown above (as do some of my friends) and find it simple and convenient.

Again, you may prefer a different brand or type of tDCS device. See my blog or do some Google searching for information on other tDCS devices in this same price category.

If you think you might want something really sophisticated, consider the foc.us V2 . I think it represents the “state of the art” in DIY brain hacking capabilities. It costs considerably more ( $299 for the V2 module ), but can be used with the cables and electrodes mentioned above.

For more information on tDCS and brain hacking, see:

http://www.speakwisdom.com
http://www.diytdcs.com
reddit.com/r/tDCS/

You should also look at:

http://www.tdcsplacements.com
speakwisdom.wordpress.com/2013/10/31/diy-tdcs-code-of-safety/

 

 

 

The Brain Hacking Revolution Continues: Introducing the foc.us Go Flow

( NOTE: The retail packaging and pricing of the Go Flow has changed as of mid-March 2016. See http://www.foc.us for details. This is part 1 of my series on the Go Flow. Parts 2 and 3 are also available at http://www.speakwisdom.com )

IMG_2912
(The Go Flow in white or gray – next to a foc.us V2)

Introduction

While preparing this blog post, I pondered what its title might be.  Here are a few of my ideas:

The New Price of Freedom (from Depression, Chronic Pain, and more) $9.99

New foc.us Go Flow tDCS Device Raises the Bar, AGAIN!

tDCS* for Everyone! The New foc.us Go Flow

Hey Medical Community. No More Excuses, Time To Get On Board.

…well, you get the idea. Foc.us has done it again – bringing to the world a really cool, very capable, tDCS device at a price that will rock the marketplace, $9.99. That’s right, not $999 or $99.99, but less than $10! Add electrodes and wires and you can have a top-notch tDCS kit for less than $30!

For those suffering with depression, chronic pain, and learning disabilities, the miracle of tDCS just became VERY affordable. This same device can also be used to enhance memory, problem solving ability, creativity, athletic ability, etc.  Ahh yes, tDCS is a wonderful thing.

And now, my oft repeated question for the medical and mental health community – when are you going to at least give tDCS a chance? You are more than happy to experiment on your patients with a variety of pharmaceuticals – frequently with poor results and nasty side-effects. Why not try something that provides great relief to some (honestly, not everyone) – without scary side-effects? Add up the annual cost to the patient of buying pharmaceuticals and follow-up care vs. the cost of a Go Flow, a few 9 volt batteries, and some oversight. Wow, are you beginning to get it?

If you are hearing about tDCS for the first time, please see my other related posts at www.speakwisdom.com or check out www.diytdcs.com for more of the basics on this great technology!

The foc.us Go Flow

The Go Flow tDCS device is a tiny module that snaps on to the top of a standard 9 volt battery. A pair of electrodes plug into the module using the same plug configuration that foc.us uses with their V2 product.

Some Key Features

  • Current delivery from 0.5 to 2 mA in 0.125 mA increments
  • Timed delivery from 5 to 35 minutes
  • Ramped Current up / down
  • Easy to use control switch and LED indicators
  • Tiny, light, rugged. Uses a standard 9 volt battery
  • Perfect for beginner, pro, home and travel use

Operation

Let’s say you want to treat depression with a Go Flow. What would a tDCS session with the Go Flow be like? Here are typical steps with some discussion along the way:

  1. Attach electrodes to the forehead area (anode on the high-left forehead, called F3, cathode on the right above the eyebrow, called FP2. See tdcsplacements.com for details.) You can use stick-on gel electrodes or wetted sponge electrodes. I discuss how to tell anode from cathode below.
  2. Plug electrode wire into the Go Flow unit
  3. Attach the Go Flow module to a 9 volt battery
  4. The Go Flow LEDs will light up in sequence as it powers up and leave you with one or more ORANGE LEDs lit, showing the amount of current for your session. The lowest LED represents 0.5 mA, the highest 2.0 mA. To change the current level slide the rocker switch UP for more current or DOWN for less.  A typical tDCS session is 1, 1.5, or 2 mA.Go Flow image 2
    (The Go Flow module showing LED display, electrode jack, and slide switch.)
  5. Once you have the desired session current set you PRESS IN on the rocker switch to move to the time setting.
  6. Session time is shown with GREEN LEDs with each representing 5 minutes of time. Slide the rocker switch UP for more time or down for less.  A typical tDCS session is 20 minutes.
  7. You are ready to begin your tDCS session! To START, PRESS IN on the rocker switch one more time.
  8. With a session in progress, the LED display will alternate between GREEN, showing time remaining, and ORANGE showing the actual delivered current level.

IMG_2929
(The Go Flow connected to my “test head” using Amrex electrodes.)

Additional Notes:

  1. You can STOP your tDCS session anytime by pressing IN on the slide switch. Current will ramp down gently to zero
  2. You can adjust current level up or down during a session. Move the slide switch up or down as desired. Each movement will change the current 0.125 mA
  3. There is no ON/OFF switch on the Go Flow. When your session is complete, UNPLUG the 9 volt battery

IMG_2919
(Wow how things have changed! Go Flow next to a DIY tDCS device I built a couple of years ago. Thank you foc.us!)

Technical Notes:

  1. I measured the current output of the two Go Flow units I have and found current to be spot on with my current selection.
  2. Maximum output voltage is 24 volts (needed to overcome electrode resistance, skin resistance, etc. This is much better than the 9 volt max of many DIY tDCS devices.
  3. Current drain on the battery is, according to my measurements, about 24 mA during a 2 mA tDCS session. It is about 13 mA for a 1 mA session.  Current drain varies somewhat depending on how many indicator LEDs are lit.
  4. A Duracell CopperTop 9 volt battery goes from 9 volts to 8 volts in 25 hours with a 10 mA load. So one could expect at least 50 to 100 tDCS sessions per battery (highly dependent on session settings.)

Go Flow inside 1
(Inside the Go Flow. Image from foc.us.)

Electrode Choices with the Go Flow

  1. foc.us has a number of electrode choices available on their web site – and third party electrodes can be used with the Go Flow, too. Foc.us supplied electrodes and cable are marked to indicate anode and cathode. Some models have a big X stamped or printed on the anode and a Y on the cathode.  With any electrodes, if you are not sure of polarity, check with a volt meter.
  2. The electrode connector in the Go Flow uses a 2.5 mm four conductor plug for its mate. From the tip of the plug (1) to base (4): 1-unused, 2-unused, 3-Y cathode, 4-X anode (which is the same as the default foc.us V2 setup.)
  3. foc.us has adapter cables and such on their web site. You can also easily build your own cables with parts from Radio-Shack, Parts Express, etc.
  4. I have a personal preference for wetted sponge-type electrodes as they can be used on skin and over hair and provide excellent conductivity.

Conclusion

The foc.us Go Flow represents a true shift in the brain stimulation and tDCS marketplace. Via this new product they provide all the capability a typical user will ever need – in a tiny, easy to use, convenient package.  The Go Flow, sold along with a good instructional video could literally change the lives of millions for the better. I’d love to travel around providing instructional seminars for medical and mental health professional showing them the Go Flow and that tDCS really is a miracle! Anyone willing to fund that?

The Go Flow can be ordered now at http://www.foc.us . Watch for Part 2 of my review of the Go Flow coming soon.

Caveat

Anyone considering the use of tDCS or any brain stimulation technology should do their homework. It’s important to understand the technology, risks, and if you should be excluded based on seizure disorder or other complications. If you are unsure you should seek the advice of a doctor, preferably one using tDCS or similar technologies in their practice.

*tDCS is transcranial direct current stimulation

 

Solid Advice on Selecting foc.us V2 Device and Accessories

Introduction

Foc.us, the London based small business that keeps innovating in the DIY tDCS* and brain stimulation space now has a number of products in their line.  Some people are confused about which parts and pieces to buy in order to have the right stuff to move ahead with a tDCS treatment (or other) program.  I thought I could help a little with this blog post.

The V2 Brain Stimulation Device

First, you will need a foc.us V2 stimulator device. The device currently sells for about $199 and with current firmware is far beyond any of the competition in terms of versatility, capability, portability, etc. I won’t take time here to list all of the MANY things the V2 can do, but suffice it to say that manufacturers of “professional grade” tDCS, tACS, etc. equipment are probably nervous about where foc.us is driving prices and capabilities! In my opinion, the V2 is THE brain stimulation device to buy at its price point.

Note: Though the V2 can be controlled via an IOS or Android device, it’s not really necessary. The V2 on-screen display and joystick will quickly and easily let you access V2 setup and features.

IMG_1530
(The foc.us V2. In my opinion, a great brain stimulation device.)

Electrodes

Next, you need electrodes. Foc.us offers FOUR different electrode options for you to choose from:

Option 1: The Gamer Headset.

IMG_1574
(The Gamer headset with sponges removed. Sponge holders can be separated from the metal band for added versatility.)

This is probably the best choice for most stimulation (tDCS) situations. It consists of two sponge electrodes mounted on a flexible band. The electrode “holders” can bend inward to place the electrodes properly on the forehead. HOWEVER, I find it best to remove the electrode holders from the band and use an elastic headband to position the electrode sponges as desired.  The Gamer headset does NOT restrict electrode placement – you just need to add your own elastic band.

IMG_1570
(Look closely at this pic and you will see the Gamer electrode holders have been removed from the included metal band. Instead they are placed on my test head using an elastic band – in this case for the savant montage.)

Option 2: The EDGE Headset.

This option should ONLY be selected IF you are interested in researching brain stimulation and its possible impact of athletic performance. This is a special-purpose (not general purpose) headset. The electrode placements are unusual and will not address the needs of most tDCS users.

img_1556
(The EDGE headset showing the main electrode at the top and the secondary electrode that would be attached to the upper arm at the bottom. This is a special purpose brain stimulation headset.)

Option 3: Moovs Stick-on Gel Electrodes

This is a new option from foc.us. It is a pair of electrodes that adhere to open areas of skin (NOT HAIR or through hair.) Because of this, they are a bit limited in terms of where they can be placed. They are light and very comfortable – and do stick to skin well. But if part of your treatment montage involves placing electrodes over hair – you should select the GAMER sponge headset (or option 4 below) instead. Remember, the Gamer electrodes can be placed anywhere with an elastic band.

150721-moovs
(The Moovs stick-on electrodes. Image from the foc.us website.)

Option 4: Your Own Electrodes

I and many other brain stimulation researchers and testers have been very pleased with the line of sponge electrodes from Amrex. Most of us use the 3×3 Amrex, but sometimes the smaller 2×2 is useful.  The Amrex sponge electrodes are not cheap, but they are built to last. Foc.us to their credit makes it EASY to use your own electrodes, whatever you prefer, via a simple adapter cable (about $10 from foc.us). The cable allows you to plug in “TENS” compatible connecting wires, including those that have banana plugs for the Amrex electrodes. You can buy electrodes, wires, and more at almost any medical supply house – and via Amazon!

amrex3x3
(The Amrex 3×3 is shown. It consists of a rubber shell, stainless wire screen, and a sponge. Connection is via a banana plug to a jack at the top of the electrode.)

Summary

The foc.us V2 represents the best capability I am aware of for DIY tDCS (and brain stimulation) users. Yes, there are many less expensive devices (tDCS) in the market and they are appropriate for those on limited budgets, just starting out with tDCS, etc. But if you want the most capability for your future brain stimulation needs, I don’t know of a better product in the market right now. Remember, you will need a foc.us V2 and electrodes.  If you buy it all from foc.us you will spend around $300.  If you choose to use your own electrodes (and connecting wires), you can spend a little less (total.)

Caveat

As I have mentioned, foc.us is a SMALL company based in London doing incredibly innovative work in the field of brain stimulation technology – with a focus (pardon the pun) on the DIY marketplace (not the multi-million dollar grant driven labs.) I believe they have become somewhat overwhelmed by their own success. So YOU may encounter slow service on any special request you make of foc.us (tech support, returns, etc.)  Be prepared to be patient. The foc.us web site also is overly complicated by its attempts to be trendy. I suggest you hit the “All Products” link at the top left as a starting point.

By the way, foc.us will not diagnose or prescribe treatment for you – so don’t be upset if they ignore such requests. Do your homework on tDCS (brain stimulation), become informed, and make your own carefully considered decisions about brain stimulation and its appropriateness for your situation.

See the following for more information on tDCS:

www.speakwisdom.com

www.diytdcs.com

www.reddit.com/r/tdcs

www.transcranialbrainstimulation.com

*tDCS is transcranial direct current stimulation

Just in Time for Back to School! Super Specific Devices tDCS!

Introduction

It’s been a very busy summer and I’m long overdue in writing a review of Super Specific Devices (SSD) line of tDCS* equipment targeting the DIY marketplace.  SSD has been quietly building some high-quality gear for several months now and their various models deserve a good look.

pic1
(The SSD Voltage Selectable tDCS Device)

The Basics

Let’s start with the basic unit – on the SSD website, you choose a unit powered by either a 9 or 12 volt battery and an analog or digital meter.

The tDCS circuit is a simple but reliable LM type current regulator with the added safety bonus of in-circuit current limiting diodes.  All components are nicely soldered to a PC board and all connections to that board are secured with glue.  SSD has chosen to build their tDCS devices into a nicely made and finished wood box – it has a more professional appearance than do many of the tDCS devices on the market today. Electrodes are connected to the device via a small “TENS” style connector on the side of the unit.

pic2
(Inside the 12 volt version of the SSD tDCS device is simple and neat. The type 23A battery can be seen to the right and the current regulator board is to the top left of the box. Approx $115)

All units are supplied with a starter set of lead-wires, non-stick electrodes, sponges, and self-adhering tape (rather than a headband).  If you are really serious about tDCS, you might want to consider the accessory banana plug adapter cord for use with Amrex and similar sponge electrodes (about $10).

 

pic3

(Operation is simple! Start with the unit turned off and the dial rotated fully counter-clockwise. Place wetted sponge electrodes as desired, turn on the unit, and adjust current to desired level. Run session for planned treatment time and at completion, rotate the dial fully counter-clockwise and turn the unit off.)

The SSD Voltage Selectable tDCS Device

Super Specific Devices also offers a new tDCS device that provides switch-selectable 9, 12, and 18 volt settings. The selectable voltage range helps deal with difficult electrode setups (like one electrode placed on the shoulder or arm, or stick-on electrodes) where a 9 volt tDCS device may not be able to overcome the higher resistance to deliver the desired current level. The ability to switch to 12 or 18 volts may make all the difference in reaching a desired treatment current level.

pic4
(The inside of the voltage selectable tDCS device is obviously more congested. A 9 volt battery powers the analog meter unit with the voltage boost circuit at the bottom left and the regulator circuit at the top center of the box.  The selector switch is at the very top left of this photo. The wiring looks more ominous than it really is. Much of the wire is related to selecting voltage and illuminating the tri-color LED appropriately. With so much point-to-point wiring, careful soldering and quality checks are a must though.)

The circuit in the voltage selectable units is again built around an LM current regulator with current limiting diode backup so maximum current cannot exceed 2.5 mA.  Interestingly the digital display version of the voltage selectable unit is USB rechargeable! According to the SSD web site, the device is switch protected so that USB energy cannot be used during a tDCS session.  This is a wise safety feature. The use of rechargeable batteries (rather than throw-away) and USB charging might be a good trend for all tDCS manufacturers to follow – just adopt the practice of isolating charging from operation as SSD has done!

pic5
(From the SSD web site. The voltage selectable, digital display, USB charging version. Approx $175)

My Testing

I have tested the 12 volt version (analog meter) and the voltage selectable version (analog meter) from Super Specific Devices and like them very much. They are solidly built using a tried and tested tDCS device design and are likely to provide reliable service for years.  Given the low price of SSD units, I can’t imagine an individual going to the trouble to find all the components and taking the time to build tDCS device(s) with this level of construction.  Time would be better spent buying and using the SSD device!

I subjected each of the SSD devices I have on hand to my usual torture and use tests. In every case, the units delivered the current level specified. In my simulated failure modes, I was never able to exceed 2.5 mA output current.

As with most tDCS vendors servicing the DIY market, SSD does not provide medical advice (diagnosis, treatment recommendations, etc.) The instructions they provide with each unit are complete in the sense of learning how to operate the supplied unit.  However, each customer is expected to seek out other sources for information on tDCS, what is possible, and treatment montages.

Final Comments

I continue to be pleased to see a wide variety of capable tDCS devices available to the public from a number of vendors.  Units span a wide range from simple and cheap to more expensive and very sophisticated.  Super Specific Devices seems to have found a niche in the middle with products that have a low price but a quality build, nice appearance, and solid features.

Super Specific Devices web site: http://www.superspecificdevices.com/

*tDCS is transcranial direct current stimulation